In general, a flush toilet is a bowl that people sit on to get rid of waste liquid or solid liquid and is generally used in most lavatories.
FIG. 1 is a schematic view showing an example of using a flush toilet, and referring to FIG. 1, a flush toilet has a toilet seat enabling a user to sit on a bowl thereof so that a user evacuates while sitting on the toilet seat.
Further, the toilet seat is rotatably coupled to the bowl for men to easily urinate after lifting the toilet seat, if necessary.
According to toilet seats of the related art, since the tops are flat planes, when a user defecates, sitting on the toilet seat, the angle between the user's back and thighs is a right angle or at least 70 degrees or more.
When a user defecates in the posture with a right angle or at least 70 degrees or more between his/her back and the thighs, the portion between the intestine and the anus is bent, so the intestinal movement is interfered with, and the intestine is blocked, if serious.
Accordingly, when a user uses the flush toilets of the related art, defecation is not easy, so the user has to exert a larger force and takes a long time to defecate.
Therefore, there is a problem that since people repeatedly defecates in a sitting posture with a right angle on flush toilets for a long period of time, in serious cases, constipation, hemorrhoids, irritable bowel syndrome, cancers, and other colorectal diseases are caused.